Jah2000

It's fine. It'll prolly go another 300k miles, and then another 300k miles, with regular maintenance.

ISADE

If you are worried about the bottom end then you should have already been getting your oil tested after oil changes. I use blackstone laboratories because it's fairly nearby, but they send you containers and you ship them back an oil sample. This tells you a lot of stuff, are you getting coolant into your oil, are you getting fuel into your oil, are you getting rod or main bearing journal material in the oil etc etc. If this comes back good don't worry about the bottom and just redo the top AFTER you confirm it's the top end with a leakdown test.

Car Analogy

Assuming leakdown confirms its top end, once head is removed you can inspect tbe bores. If no serious scoring or out of round, you're good.

Its the cylinder walls that make these engines not rebuildable. Pistons, rings, bearings can all be replaced and be reliable, so long as correct size bearing color codes are used. Cranks are expensive and hard to find good ones. So long as you don't loose a bearing (likemrod.knock, etc) your crank will probably be fine.

So if head comes off and you find heavy cylinder scoring, then yeah, maybe rebuilding head isn't worth it, as block doesn't have a long healthy life ahead of it. But so long as cylinder walls still decent, go for it.